Perhaps you should try some spelling variations:
tang hanh » tang thanh, dang hanh, nang hanh
van trieu » tan trieu, van tieu, van hieu
toc sach » hoc sach, doc sach, thuoc sach
duc tang » duc thang, duc tan, tuc tang
nang xa » nang x, lang xa, nang ma
hieu ve » hieu van
hieu va » lieu va, hieu qua
cam duc » cam xuc, cao duc, pham duc

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) OR (toc sach)) ky nang xa hoi. ((hieu ve) or (hieu va)) cam duc tang hanh vi van trieu~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (toc sach)) ky nang xa hoi. ((hieu ve) OR (hieu va)) cam duc tang hanh vi van trieu.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) OR (toc sach)) ky nang xa hoi. ((hieu ve) or (hieu va)) cam duc tang hanh vi van trieu".
• Adding a wildcard symbol may retrieve word variants: ((te sach) OR (toc sach)) ky nang xa hoi. ((hieu ve) or (hieu va)) cam duc tang hanh vi van trieu*.